1. Field of the Invention
The present invention relates to a vertically oriented image scanning device, and in particular to a vertically oriented image scanning device incorporating a document retainer for securely and properly positioning a document on a scanning window of the image scanning device.
2. Description of the Prior Art
Most of the scanners available in the markets are so called “flat-bed” scanner which comprises a chassis laid flat on for example a desk with a horizontal scanning window on which a document to be scanned is positioned. The document can be retained in position on the scanning window by gravity. The flat-bed scanner, however, occupies a great area of the desk surface, causing a great waste of space of limited office space. This is of particular concern in urban areas where office rent is high.
A vertically oriented image scanning device effectively reduces the desk space required for accommodation by providing a stand-up chassis with a vertically arranged scanning window. Although desk space is effectively saved for accommodating a vertically oriented image scanning device, documents to be scanned cannot be properly and securely retained on the scanning window due to the vertical arrangement of the scanning window. A flap cover is commonly seen in both flat-bed scanners and vertically oriented image scanning devices. Such a flap cover, however, cannot help in effectively and precisely positioning the document on the vertical scanning window of a vertically oriented image scanning device. As a consequence, the scanning quality of a vertically oriented image scanning device cannot be effectively improved.
It is thus desired to have a vertically oriented image scanning device comprising a document retainer for effectively and securely positioning a document on a vertical scanning window of the vertically oriented image scanning device.